These files are in Rich Release Format (RRF) and do not require the use of the MetamorphoSys program provided with the UMLS Knowledge Sources Files. The character set of RxNorm release files is Unicode UTF-8. If you need assistance with these files, please e-mail the RxNorm team at: rxnorminfo@nlm.nih.gov. Please read the README file for the release, which is contained in the release zip package. For additional information about RxNorm releases, including scripts for loading the RxNorm data into Oracle and MySQL databases, read the RxNorm Documentation.

For users who wish to automate the download of the RxNorm releases, we created scripts for Windows and Mac/Linux/Solaris computers that, when combined with a scheduling tool, will allow you to automate your downloads. You can download the scripts, along with a README file with instructions, here: http://download.nlm.nih.gov/rxnorm/terminology_download_script.zip